打顶及仿生信号分子对不同烤烟品种氧化胁迫的影响

为研究仿生型信号分子（BSM）对不同烤烟品种氧化胁迫的影响，选取云烟87、翠碧1号（CB-1）、K326三个烤烟品种为供试对象，对不打顶（CK）、打顶（T1）及打顶后立即涂抹BSM（T2）不同处理后烤烟植株中超氧阴离子（O2-．）、过氧化氢（H2O2）、丙二醛（MDA）的含量及超氧化物歧化酶（SOD）活性进行测定。结果表明，打顶后6h，云烟87、CB-1与K326的O2-．、H2O2含量较CK均表现出增加；96h后，3个烤烟品种的SOD活性亦较CK增强、MDA含量增加，说明打顶这种机械损伤使烟草植株出现了氧化胁迫。打顶后涂抹BSM，云烟87中的O2-、H2O2、MDA含量增加、SOD酶活性下降；而CB-1及K326中O2-．、H2O、MDA含量降低，SOD酶活性提高；表明BSM对CB-1及K326打顶后的氧化胁迫有缓解作用而对云烟87没有表现出缓解作用。

Effects of Topping and Bionics Signal Molecule on Oxidation Stress of Different Flue-cured Tobacco Varieties

To study the effects of bionics signal molecule （BSM） on oxidative stress of different flue-cured tobacco varieties, Yunyan87, Cuibi-1 （CB-1） and K326 were used. Plants were treated with not topping （CK）, topping （T1） and topping-BSM （T2）. The contents of superoxide anion （O2-.）, hydrogen peroxide （H2O2）, malondialdehyde （MDA） and the activity of superoxide dismutase（SOD） in flue-cured tobacco were measured. The results showed that, compared with CK, the contents of O2.and H2O2 increased after 6 h of topping in Yunyan87, Cuibi-1（CB-1） and K326. The SOD activity and the MDA concentration increased after 96 h, which entailed that mechanical damage, e.g. topping, could result in plant oxidative stress. In the treatment of BSM after topping, the contents of O2-., H2O2 and MDA in Yunyan87 increased, but the activity of SOD decreased. However, the contents of O2-., H2O2 and MDA in CB-1 and K326 decreased, but the activity of SOD increased. Therefore, BSM could effectively alleviate the oxidative stress caused by topping in CB-1 and K326, but not in Yunyan87.